Tegra: fdt: tamonten: Add common tamonten.dtsi file from linux

Tamonten boards (medcom-wide, plutux, and tec) use a different/new
dtsi file w/common settings.

Signed-off-by: Tom Warren <twarren@nvidia.com>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>